This invention relates to a method for impregnating a ceramic material such as a carbonaceous material or carbon material with an impregnation liquid and a product produced thereby.
A carbonaceous material is a typical example of various ceramic materials used as a structural material or a material for machines. Such a carbonaceous material is a good thermal and electric conductor and has an excellent thermal resistance. In particular, its strength does not decrease at high temperatures.
On the other hand, the carbonaceous materials are porous. Thus, they do not have a good mechanical strength. Also, they are easily oxidized and therefore consumable.
In view of the foregoing, many researchers have tried to obtain a high density carbonaceous material which maintains it excellent characteristics for a long period of time. For example, dense particles are packed with a high density.
In another conventional method, pores of a carbonaceous material are impregnated with an impregnation liquid such as pitch. For instance, a shaped carbonaceous material and an impregnation liquid are set in a container. Pressurized air is applied directly to the impregnation liquid in such a way that the pores of the carbonaceous material are impregnated with the impregnation liquid to thereby produce a high density carbonaceous material. The impregnation liquid is heated at 80.degree. C. or more. The pressure of the pressurized air is 20 Kg/cm.sup.2 or less. In such a conventional method, however, the density of the carbonaceous material is not sufficiently high. The impregnation is not satisfactory.